Germany and Bayern Munich midfielder Sebastian Deisler has announced his retirement from football at the age of 27 after a string of knee problems.

Deisler missed the 2006 World Cup after undergoing a fifth operation on his knee and he has also suffered from depression throughout his career.

"I no longer have any real faith in my knee. It's been an ordeal," he said.

"I can no longer play with the right level of enjoyment and I don't do anything by halves."

If he feels in condition at some time in the future he can always come back

Bayern manager Uli Hoeness

Deisler's combination of speed, dribbling and crossing ability meant he was tipped for greatness after making his Bundesliga debut as an 18-year-old for Borussia Moenchengladbach in 1998.

He won the first of his 36 international caps two years later but injuries kept him out of the 2002 World Cup.

Deisler missed much of the 2003-04 season to have treatment for depression but looked to be in better mental shape and back to his best when he returned.

But another knee injury, which he suffered in training in 2006, ended his chances of playing in last year's World Cup and, although he made a handful of appearances this season, he decided it was time to quit.